yes, you should have an electrical plan beforehand. that said, a lot of it is either code-determined or sense driven. For example, switches are inside of doors and outlets are located every x feet.

Unless it is a load bearing wall or specific locations for recessed fixtures in the ceiling, I would not get that bent up about the framing as studs can be cut out/moved if required for'perfect' positioning.

However, that being said it is very common practice to alter the location of an outlet box by the width of a 2 x 4. For example, one typically needs an outlet near a door entrance. However sticking a box on the outside of the king stud may not be the most ideal location, particularly if you're using wide trim since they could interfere. Thus electricians will nail one or more short scrap 2 x 4's to the existing stud to create a nailing surface for the box further away from the existing stud. If you need things more precise that 1.5" increments, the same philosophy can be used with any sized lumber.